Gassed in the face

[1911cherry]

I loaded up 100 plinkers for my Chinese Type 53 , assorted brass, large magnum pistol primers ,6 gr of longshot over a Lee 312-185-2r. These were made of mixed wheel weight, watercooled ,gas checked, homemade lube, heavy on the beeswax, and measure .315. Shooting along at a nice slow pace , grouping 1-1/2 inches at 50 yards- best so far- then it got me- gas around the bolt. Three rounds out of 100 did this, all the same brand of brass. All have a nice sooty neck on them, should I have fired a more powerful charge to form the brass first before plinking with it? The Mosin vents straight back in my face so I would really like to avoid this in the future. What did I do wrong.....

[3006guns]

I'm not familiar with that powder, but it sure sounds like a case of low pressure to me. The neck and shoulder area doesn't seem to be expanding and acting like a seal as it was designed, so you may need to increase your charge or change powders to something a little faster.

[Larry Gibson]

All have a nice sooty neck on them, should I have fired a more powerful charge to form the brass first before plinking with it?

The answer is in your own question......yes you should have. With such loads many of us also leave the case mouth flair to help seal the chamber. It takes about 7,000 psi to expand/obturate a case, give or take, to seal the chamber and a bit of a time/pressure curve to keep the chamber sealed while the bullet gets out of the barrel. You have neither with those kinds of loads.

Larry Gibson

[sthwestvictoria]

From page 142 - Bolt Action Rifles Third Ed by Frank de Haas with regard to the Mosin Nagant design:

[tomme boy]

I have had a bunch of cases rupture on a older M44 I used to have. The ammo was Albanian brass surplus and a few steel Czech surplus. It blows right into your face and eye. Make sure to wear safety glasses when shooting these Mosins.

[Multigunner]

Maybe try once fired with full load cases annealed at neck and shoulder before reloading.

[Der Gebirgsjager]

Yup! I agree with most of what's been said. Your load is too light to seal the brass against the walls of the chamber. Same thing has happened to me with .30-40 Krag and .303 British. The sooty case neck is always the giveaway. Longshot probably isn't your best bet anyway. I'd try some IMR 4895 in the mid-20 grains.

[Dutchman]

Highly recommend these very good inexpensive safety glasses for shooting cast bullets.

http://www.ebay.com/sch/i.html?_from...asses&_sacat=0

I use them in the machine shop but found the coverage to be excellent for shooting.

They have interchangable lenses, amber, polarized and clear. They make darn good sun glasses, too. The arms are adjustable, too.

Here's the amber version:
http://www.ebay.com/itm/UVEX-Astrosp...item19ebae1dc7
$8 delivered. You don't need to spend big bucks on SAFE shooting glasses.

I got carried away once and bought 8 pair of these with the different lenses and frames. Didn't want to get caught without any.

Dutch

[1911cherry]

Yep, it was my fault that's what I thought, would a charge of 16 grs of 2400 be enough pressure to get a good seal? I got an 8lb can in a barter and have no magnum pistols to load for.

[nicholst55]

I have had a few rounds of milsurp Mosin fodder split the cases, but I was fortunate. First, I wear safety glasses. Second, all the gas escaped from the various joints in the bolt, and I didn't get a face full of gas. I broke down the remainder of that can of ammo - 1953 Bulgarian Light Ball, and am shooting the bullets in Winchester brass.

[WILCO]

Yep, it was my fault that's what I thought, would a charge of 16 grs of 2400 be enough pressure to get a good seal?

Give this sticky a read: http://castboolits.gunloads.com/show...Rifles-Article

Been where you've been on this. Hasn't happened since I learned a few things.

[Eddie2002]

I had the same thing happen when I pulled down some steel cased ammo and reloaded it with 6 grains of Greendot pushing a 100 grain plinker. The necks of the cases were all sooted up an I got a little blowback from the bolt area. The load worked with brass cases, looks like the steel cases were a lot tougher.

[leadman]

I don't go under 10grs of a fast shotgun/pistol powder in a full size case like the 30-06, 303, 7.62X54R, 7.65 Arg, etc. This way I make sure the boolit goes out the barrel and the case seals the gas in the chamber.
Fire forming first and leaving part of the flare if possible does help.

[CHeatermk3]

you have a keg of 2400 and shoot cast in a Mosin?

Sounds like fat city to me!!

[1911cherry]

Yeah I gotta cast a lot of boolits cause I have to fed a 44 Izhevesk 91-30, a sporterized M44 Izhevesk, and a T-53 too. I am working on a load to hunt deer with in the sporter ,gotta zero my peep sight maybe Ill be ready for the season opener.